The biological effects of gamma radiation may exert damage beyond that of the individual through its deleterious effects on reproductive function. Impaired reproductive performance can result in reduced population size over consecutive generations. In a continued effort to investigate reproductive and heritable effects of ionizing radiation, we recently demonstrated adverse effects and genomic instability in progeny of parents exposed to gamma radiation. In the present study, genotoxicity and effects on the reproduction following subchronic exposure during a gametogenesis cycle to ⁶⁰Co gamma radiation (27 days, 8.7 and 53 mGy/h, total doses 5.2 and 31 Gy) were investigated in the adult wild-type zebrafish (Danio rerio). A significant reduction in embryo production was observed one month after exposure in the 53 mGy/h exposure group compared to control and 8.7 mGy/h. One year later, embryo production was significantly lower in the 53 mGy/h group compared only to control, with observed sterility, accompanied by a regression of reproductive organs in 100% of the fish 1.5 years after exposure. Histopathological examinations revealed no significant changes in the testis in the 8.7 mGy/h group, while in 62.5% of females exposed to this dose rate the oogenesis was found to be only at the early previtellogenic stage. The DNA damage determined in whole blood, 1.5 years after irradiation, using a high throughput Comet assay, was significantly higher in the exposed groups (1.2 and 3-fold increase in 8.7 and 53 mGy/h females respectively; 3-fold and 2-fold increase in 8.7 and 53 mGy/h males respectively) compared to controls. A significantly higher number of micronuclei (4–5%) was found in erythrocytes of both the 8.7 and 53 mGy/h fish compared to controls. This study shows that gamma radiation at a dose rate of ≥ 8.7 mGy/h during gametogenesis causes adverse reproductive effects and persistent genotoxicity (DNA damage and increased micronuclei) in adult zebrafish.

伽玛射线的生物学作用可能通过对生殖功能的有害作用，使损害超出个人的范围。生殖能力受损可导致连续几代人的种群减少。在继续努力研究电离辐射的生殖和遗传效应的过程中，我们最近证明了暴露于伽玛射线的父母的后代中的不利影响和基因组不稳定。在本研究中，研究了成年野生型斑马鱼在配子发生周期中亚慢性暴露于配子⁶⁰ Coγ射线辐射（27天，8.7和53 mGy / h，总剂量5.2和31 Gy）后的遗传毒性和对生殖的影响。（Danio rerio）。与对照组和8.7 mGy / h相比，在53 mGy / h的暴露组中，暴露一个月后观察到胚胎产量显着降低。一年后，在53 mGy / h组中，与对照组相比，胚胎产量明显低于对照组，并且具有不育性，并且在暴露1.5年后，有100％的鱼类生殖器官退化。组织病理学检查显示，在8.7 mGy / h组中，睾丸无明显变化，而在暴露于该剂量率的女性中，有62.5％的卵子发生仅在早期玻璃体形成阶段。使用高通量彗星分析法在辐射后1.5年在全血中测定的DNA损伤在暴露组中显着更高（8.7和53 mGy / h雌性分别增加1.2和3倍； 3倍和2倍女性）倍数增加8。与对照组相比，男性分别为7和53 mGy / h）。与对照组相比，在8.7和53 mGy / h的鱼类的红细胞中发现的微核数量显着更高（4–5％）。这项研究表明，在配子发生过程中，γ射线辐射的剂量率≥8.7 mGy / h会对成年斑马鱼产生不利的生殖作用和持续的遗传毒性（DNA损伤和微核增加）。